Transport networks such as optical networks generally comprise Optical Transport Network (OTN), Wavelength-Division Multiplexing (WDM), Synchronous Digital Hierarchy (SDH) or Synchronous Optical Network (SONET), which have already been widely applied in telecommunication field at present.
Automatic Switched Transport Network (ASTN) has become a research hotspot in the field of the transport network in recent years. The concept of the ASTN is brought forward in the ITU-T G.8080 recommendation, in which a specific Control Plane (CP) is set to achieve the function of the ASTN network. The maintenance of the binding state of each Sub-Network Point (SNP) by the TAP is described in the ITU-T G.8080 recommendation.
The X.731 issued by the CCITT (former name of the ITU-T) describes the general state of a managed object, which includes management state (including locked, unlocked and shutting down), resource use state (including idle, active and busy), and operational state (enable and disable).
After the transport network has been developed into the ASTN, the state thereof can generally not be synchronized with the general state described in the X.731 due to the lack of a perfect definition of the SNP binding state, and the lack of a notification of SNP binding state. Technical solutions enabling the maintenance of SNP binding state and the synchronization thereof with the general state described in the X.731 are therefore urgently needed, but no related solution has been brought forward so far.